The format of the given string is `[a-z]/[0-9]{8}/[0-9]{6}`. It can be split into three parts: 1. The first part is a single letter, denoted by `[a-z]`. 2. The second part is an 8-digit number, denoted by `[0-9]{8}`. 3. The third part is a 6-digit number, denoted by `[0-9]{6}`. Example: The string `a/20180815/122924` can be split into the following parts:
- First part: `a`
- Second part: `20180815`
- Third part: `122924`